INTERNAL COMBUSTION EXGIXE [CHAP, rx

mhffi they aiv applied to the propulsion of vehicles and boats
ctivrly ? " (Mech. Sc. Tripos, 1913.)

Whv Is the power of the engine of a motor car so great in com-
on \\lth the power applied to a horse-drawn vehicle ? Give a
i intimate of how the power of a car rated at 38 H.P. is spent—

111 When going at 80 m.p.h. on the level.

i2) When going at slow speed up a hill of 1 in 5.
t is the probable loss attributable to the crankshaft, the gear
the axle ?

27. the accelerations of the piston of an engine at the ends

oftho^wkearegivenbywVn-j-y-Wherewisthe angular velocity of

T I are the lengths of crank and connecting rod.
(Mech. Sc. Tripos, 1912.)

28. following are the results of two comparative tests of the
gas the only difference between the two being that in

B the gas cock was opened wider than in test A, and the power
correspondingly greater :—

A B

Vol. of gms per stroke (cu. ft.) . . . 0-10 O-13

per stroke (per cent, of heat supply) . 30 27

Heat .given to jacket water (per cent, of heat supply) . 29 34

The of the gas was complete in both cases. What is

the of (I) the greater percentage heat loss in B, and (2)

thermal efficiency in B T

Is the heat loss adequate to account for the whole of the

ia efficiency, and* if not, haw do you account for the balance ?

(Mech. Sc. Tripos, 1913.)

29. that tli© force required to accelerate the reciprocating
of an is given approximately by

M»V (cos $+-v cos 2 0L

I

If sas of reciprocating parts.

a =3= velocity of crank.

r = crank radius.

I = length of eonnectrng rod,

i 3=5 angle, measured from line of stroke.

any method by which the acceleration of the recipro-

cating may be obtained. (B. of E., 1912.)

3d there is no change of temperature when a perfect

through a throttle valve, has. been again brought to

with hydrogen, ha-v© shown" a very slight rise of tern-
wouM you aooount for this ?
(l!ech,*So. JHpos, 1912.)